Difficulty: 2 / 5
Step 1 - In a deep saucepan, stir together stock, lemongrass, galangal, arbol pepper, garlic,and kaffir lime leaves. Bring to a boil and then simmer for 5-6 minutes to infuse the broth.
Step 2 - Stir in remaining ingredients (except chili pepper, quartered limes and cilantro)and stir to combine. Simmer soup for 5-7 minutes to cook prawns. Taste soup for balance of sour, sweet, saltiness and heat, then divide into 4 bowls and top with handfuls of torn cilantro and chili pepper, as desired and extra lime wedges for extra lime if needed.